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Hello everybody: please help me: (no convergence)
Posted 19.10.2010, 19:01 GMT-4 3 Replies
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I always get these two message in my simulation with comsol 3.5a
1st: Failed to find a solution:
Divergence of the linear iterations.
Returned solution has not converged
2nd:
Failed to find a solution:
The relative residual is greater than the relative tolerance, for the direct solver.
Returned solution has not converged.
my simulation is in quasi-static electromagnetic analysis and I used almost all of solvers: GMRES, FGMRES and any kinds of pre- and post-conditioners.
Is it because of solver or meshing?
1st: Failed to find a solution:
Divergence of the linear iterations.
Returned solution has not converged
2nd:
Failed to find a solution:
The relative residual is greater than the relative tolerance, for the direct solver.
Returned solution has not converged.
my simulation is in quasi-static electromagnetic analysis and I used almost all of solvers: GMRES, FGMRES and any kinds of pre- and post-conditioners.
Is it because of solver or meshing?
3 Replies Last Post 20.10.2010, 18:11 GMT-4
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Posted:
1 decade ago
I would suggest always to start with a simple model and simpler solvers than iterative solvers. Use Pardiso solver, or if your model is not too large use MUMPS solver, which is even more robust.
movaffagh bashi,
danial
--
Comsol 4.0a
Ubuntu 10.04.1
movaffagh bashi,
danial
--
Comsol 4.0a
Ubuntu 10.04.1
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
Be sure that your boundary conditions are well defined and you have consistent units for material properties.
Regards,
Özen
Regards,
Özen
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Posted:
1 decade ago
I checked everything again and I changed the B-H curve into consistent mur which has had effect and the solution goes up to 99% but error in this moment with:
with GMRES solver relative tolerance is 1.9e-5 with relative residual 4.9e-8 so it again says:
failed to find a solution
the relative error is greater than the relative tolerance, for the direct solver
returned solution has not converged
but some answers are logical e.g voltage distribution but not magnetic field density.
Do you think it is because of importing the shape from another software. is the relative tolerance of importing important?
with GMRES solver relative tolerance is 1.9e-5 with relative residual 4.9e-8 so it again says:
failed to find a solution
the relative error is greater than the relative tolerance, for the direct solver
returned solution has not converged
but some answers are logical e.g voltage distribution but not magnetic field density.
Do you think it is because of importing the shape from another software. is the relative tolerance of importing important?